affine-quads.c

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/*
 
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// Phase-17 affine UV-mapping quad suite. Five 4-vertex flat-textured
// quads spanning the parameter space:
//
//   Q1 axis-aligned 1:1 baseline
//   Q2 90 degree UV rotation
//   Q3 trapezoid (non-parallelogram, top-width != bottom-width)
//   Q4 skewed non-parallelogram (every edge non-axis-aligned)
//   Q5 compressed UV on large quad
//
// These tests primarily validate that the 4-vert path produces
// hardware-matching output across non-trivial geometries. Hardware
// decomposes a quad into two triangles natively; if the 4-vert sweep
// diverges from a (1,3,2)+(0,1,2) decomposition output in ways
// hardware doesn't, that's evidence to retire the 4-vert sweep
// entirely. Q4 in particular probes the diagonal-seam class where
// phase-8's QFD finding showed a single seam-gap pixel.
 
// clang-format off
 
CESTER_BODY(
 
// ---- Q1 AQ_AXIS_BASE -----------------------------------------------------
// v0=(5,5)/(0,0)  v1=(20,5)/(15,0)  v2=(5,15)/(0,10)  v3=(20,15)/(15,10)
// Axis-aligned 1:1. Baseline correctness.
 
static void drawAQ_AXIS_BASE(void) {
    rasterReset();
    rasterClearTestRegion(0, 0, 24, 16);
    setTexpage(TEX17_TX, TEX17_TY, 2);
    setTextureWindow(0, 0, 0, 0);
    rasterFlatTexQuad(TEX_MOD_NEUTRAL,
                      5,  5,  0,  0,
                      20, 5,  15, 0,
                      5,  15, 0,  10,
                      20, 15, 15, 10,
                      TEX17_CLUT_FIELD, TEX17_TPAGE);
    rasterFlushPrimitive();
}
 
// ---- Q2 AQ_TWIST_90 ------------------------------------------------------
// v0=(5,5)/(0,0)  v1=(20,5)/(0,15)  v2=(5,18)/(13,0)  v3=(20,18)/(13,15)
// 90 degree UV rotation. dU/dX = 0 along v0-v1, dU/dY = 1 along v0-v2.
// Decomposition's per-triangle UV interpolation has to match at the
// (v1, v2) diagonal seam.
 
static void drawAQ_TWIST_90(void) {
    rasterReset();
    rasterClearTestRegion(0, 0, 24, 20);
    setTexpage(TEX17_TX, TEX17_TY, 2);
    setTextureWindow(0, 0, 0, 0);
    rasterFlatTexQuad(TEX_MOD_NEUTRAL,
                      5,  5,  0,  0,
                      20, 5,  0,  15,
                      5,  18, 13, 0,
                      20, 18, 13, 15,
                      TEX17_CLUT_FIELD, TEX17_TPAGE);
    rasterFlushPrimitive();
}
 
// ---- Q3 AQ_TRAPEZOID -----------------------------------------------------
// v0=(8,5)/(0,0)  v1=(20,5)/(15,0)  v2=(5,18)/(0,13)  v3=(23,18)/(15,13)
// Top edge 12 wide, bottom 18 wide. Per-row pixel-count varies linearly.
// Stresses both decomposed triangles having different X spans per row.
 
static void drawAQ_TRAPEZOID(void) {
    rasterReset();
    rasterClearTestRegion(0, 0, 32, 20);
    setTexpage(TEX17_TX, TEX17_TY, 2);
    setTextureWindow(0, 0, 0, 0);
    rasterFlatTexQuad(TEX_MOD_NEUTRAL,
                      8,  5,  0,  0,
                      20, 5,  15, 0,
                      5,  18, 0,  13,
                      23, 18, 15, 13,
                      TEX17_CLUT_FIELD, TEX17_TPAGE);
    rasterFlushPrimitive();
}
 
// ---- Q4 AQ_SKEW_NP -------------------------------------------------------
// v0=(5,5)/(0,0)  v1=(20,8)/(12,0)  v2=(8,22)/(0,12)  v3=(25,18)/(12,12)
// Every edge non-axis-aligned. Diagonal seam between (v1, v2) bisects
// interior. Phase-8 QFD found one seam-gap pixel on a parallelogram;
// arbitrary skew may surface more.
 
static void drawAQ_SKEW_NP(void) {
    rasterReset();
    rasterClearTestRegion(0, 0, 32, 24);
    setTexpage(TEX17_TX, TEX17_TY, 2);
    setTextureWindow(0, 0, 0, 0);
    rasterFlatTexQuad(TEX_MOD_NEUTRAL,
                      5,  5,  0,  0,
                      20, 8,  12, 0,
                      8,  22, 0,  12,
                      25, 18, 12, 12,
                      TEX17_CLUT_FIELD, TEX17_TPAGE);
    rasterFlushPrimitive();
}
 
// ---- Q5 AQ_COMPRESS_UV ---------------------------------------------------
// v0=(5,5)/(0,0)  v1=(30,5)/(8,0)  v2=(5,22)/(0,5)  v3=(30,22)/(8,5)
// 25x17 screen -> 8x5 UV. Texture stretched. Fractional UV step
// across decomposition seam.
 
static void drawAQ_COMPRESS_UV(void) {
    rasterReset();
    rasterClearTestRegion(0, 0, 32, 24);
    setTexpage(TEX17_TX, TEX17_TY, 2);
    setTextureWindow(0, 0, 0, 0);
    rasterFlatTexQuad(TEX_MOD_NEUTRAL,
                      5,  5,  0, 0,
                      30, 5,  8, 0,
                      5,  22, 0, 5,
                      30, 22, 8, 5,
                      TEX17_CLUT_FIELD, TEX17_TPAGE);
    rasterFlushPrimitive();
}
 
)  // CESTER_BODY
 
// --------------------------------------------------------------------------
// Q1 AQ_AXIS_BASE assertions
// --------------------------------------------------------------------------
 
CESTER_TEST(aq_axis_base_8_8, gpu_raster_phase17,
    drawAQ_AXIS_BASE();
    PHASE17_ASSERT_PIXEL_EQ(EXPECT_AQ_AXIS_BASE_8_8, 8, 8);
)
 
CESTER_TEST(aq_axis_base_15_10, gpu_raster_phase17,
    drawAQ_AXIS_BASE();
    PHASE17_ASSERT_PIXEL_EQ(EXPECT_AQ_AXIS_BASE_15_10, 15, 10);
)
 
CESTER_TEST(aq_axis_base_5_14, gpu_raster_phase17,
    drawAQ_AXIS_BASE();
    PHASE17_ASSERT_PIXEL_EQ(EXPECT_AQ_AXIS_BASE_5_14, 5, 14);
)
 
CESTER_TEST(aq_axis_base_20_5_v1_excluded, gpu_raster_phase17,
    drawAQ_AXIS_BASE();
    PHASE17_ASSERT_PIXEL_EQ(EXPECT_AQ_AXIS_BASE_20_5, 20, 5);
)
 
// --------------------------------------------------------------------------
// Q2 AQ_TWIST_90 assertions
// --------------------------------------------------------------------------
 
CESTER_TEST(aq_twist_90_8_10, gpu_raster_phase17,
    drawAQ_TWIST_90();
    PHASE17_ASSERT_PIXEL_EQ(EXPECT_AQ_TWIST_90_8_10, 8, 10);
)
 
CESTER_TEST(aq_twist_90_15_13, gpu_raster_phase17,
    drawAQ_TWIST_90();
    PHASE17_ASSERT_PIXEL_EQ(EXPECT_AQ_TWIST_90_15_13, 15, 13);
)
 
CESTER_TEST(aq_twist_90_12_8_near_seam, gpu_raster_phase17,
    drawAQ_TWIST_90();
    PHASE17_ASSERT_PIXEL_EQ(EXPECT_AQ_TWIST_90_12_8, 12, 8);
)
 
CESTER_TEST(aq_twist_90_12_11_near_seam, gpu_raster_phase17,
    drawAQ_TWIST_90();
    PHASE17_ASSERT_PIXEL_EQ(EXPECT_AQ_TWIST_90_12_11, 12, 11);
)
 
// --------------------------------------------------------------------------
// Q3 AQ_TRAPEZOID assertions
// --------------------------------------------------------------------------
 
CESTER_TEST(aq_trapezoid_12_8, gpu_raster_phase17,
    drawAQ_TRAPEZOID();
    PHASE17_ASSERT_PIXEL_EQ(EXPECT_AQ_TRAPEZOID_12_8, 12, 8);
)
 
CESTER_TEST(aq_trapezoid_14_13, gpu_raster_phase17,
    drawAQ_TRAPEZOID();
    PHASE17_ASSERT_PIXEL_EQ(EXPECT_AQ_TRAPEZOID_14_13, 14, 13);
)
 
CESTER_TEST(aq_trapezoid_8_15, gpu_raster_phase17,
    drawAQ_TRAPEZOID();
    PHASE17_ASSERT_PIXEL_EQ(EXPECT_AQ_TRAPEZOID_8_15, 8, 15);
)
 
CESTER_TEST(aq_trapezoid_20_15, gpu_raster_phase17,
    drawAQ_TRAPEZOID();
    PHASE17_ASSERT_PIXEL_EQ(EXPECT_AQ_TRAPEZOID_20_15, 20, 15);
)
 
// --------------------------------------------------------------------------
// Q4 AQ_SKEW_NP assertions
// --------------------------------------------------------------------------
 
CESTER_TEST(aq_skew_np_12_10, gpu_raster_phase17,
    drawAQ_SKEW_NP();
    PHASE17_ASSERT_PIXEL_EQ(EXPECT_AQ_SKEW_NP_12_10, 12, 10);
)
 
CESTER_TEST(aq_skew_np_15_14, gpu_raster_phase17,
    drawAQ_SKEW_NP();
    PHASE17_ASSERT_PIXEL_EQ(EXPECT_AQ_SKEW_NP_15_14, 15, 14);
)
 
CESTER_TEST(aq_skew_np_10_15, gpu_raster_phase17,
    drawAQ_SKEW_NP();
    PHASE17_ASSERT_PIXEL_EQ(EXPECT_AQ_SKEW_NP_10_15, 10, 15);
)
 
CESTER_TEST(aq_skew_np_18_12_seam, gpu_raster_phase17,
    drawAQ_SKEW_NP();
    PHASE17_ASSERT_PIXEL_EQ(EXPECT_AQ_SKEW_NP_18_12, 18, 12);
)
 
// --------------------------------------------------------------------------
// Q5 AQ_COMPRESS_UV assertions
// --------------------------------------------------------------------------
 
CESTER_TEST(aq_compress_uv_10_8, gpu_raster_phase17,
    drawAQ_COMPRESS_UV();
    PHASE17_ASSERT_PIXEL_EQ(EXPECT_AQ_COMPRESS_UV_10_8, 10, 8);
)
 
CESTER_TEST(aq_compress_uv_20_15, gpu_raster_phase17,
    drawAQ_COMPRESS_UV();
    PHASE17_ASSERT_PIXEL_EQ(EXPECT_AQ_COMPRESS_UV_20_15, 20, 15);
)
 
CESTER_TEST(aq_compress_uv_15_10, gpu_raster_phase17,
    drawAQ_COMPRESS_UV();
    PHASE17_ASSERT_PIXEL_EQ(EXPECT_AQ_COMPRESS_UV_15_10, 15, 10);
)
 
CESTER_TEST(aq_compress_uv_29_21, gpu_raster_phase17,
    drawAQ_COMPRESS_UV();
    PHASE17_ASSERT_PIXEL_EQ(EXPECT_AQ_COMPRESS_UV_29_21, 29, 21);
)